The invention relates to a device for discharging exhaust air from the surroundings of a metal strip. Moreover, the device relates to a roll train having at least two rolling stands for rolling the metal strip by way of the device according to the invention.
Devices of the stated type are fundamentally known in the prior art, for example from the guideline VDI 2262 Sheet 4/Part 4, page 58, figure 37 and associated description. A container with a liquid for dip coating a workpiece is disclosed there. A blower is arranged on one side above the container for generating an air flow for conveying exhaust air in the form of air pollutants which rise up from the bath, in a blowing direction. The blowing direction aims over the bath at the other side of the industrial bath container, where an extraction device is arranged for extracting and discharging the air flow with the exhaust air, which air flow is generated by the blower. The blowing direction is oriented transversely with respect to a conveying direction of a workpiece to be coated when the latter dips into the container or is conveyed out of said container after being coated.
German patent document DE 199 16 233 C1 discloses a device for discharging exhaust air from the surroundings of a rolling stand for rolling, in particular for cold rolling a metal strip. The rolling stand is enclosed completely with an air inlet opening and an air outlet opening. A blower is provided for generating an air flow in a direction with a component transversely with respect to the conveying direction of the metal strip. Another component of the movement direction of the air flow can be directed perpendicularly with respect to the plane of the metal strip, with the result that the air flow overall runs obliquely with respect to the metal strip. Furthermore, an extraction device is provided which lies opposite the blower in the direction of the air flow, for extracting and discharging the air flow which is generated by the blower together with exhaust air in the surroundings of the metal strip, which exhaust air is entrained by the air flow.